docs: def dump_stats(self):
          """Logs statistics of our operation."""
          log.info('Dumping statistics:')
          stats = []
          stats.append(
              'client-request-errors {}'.format(self._client_request_errors))
          stats.append('denied-allocations {}'.format(self._denied_allocations))
          stats.append('num-ports-managed {}'.format(self._port_pool.num_ports()))
          stats.append('num-ports-checked-for-last-request {}'.format(
              self._port_pool.ports_checked_for_last_request))
          stats.append('total-allocations {}'.format(self._total_allocations))
          for stat in stats:
              log.info(stat)